Just thought the forum here might be interested in this:
http://www.udk.com/
http://udn.epicgames.com/Main/WebHome.html
http://udn.epicgames.com/Three/DevelopmentKitHome.html
I might be looking into this for my Earthdawn project. I like that there always the option to buy a commercial license if you want to start marketing and selling your project.